NASA finds Earth-size world in habitable-zone
NASA finds Earth-size world in habitable-zone

WASHINGTON — NASA's Transiting Exoplanet Survey Satellite, or 'TESS' mission, devised to specifically find Earth-sized planets orbiting nearby stars has identified TOI 700 d as a potential candidate occupying a star's habitable zone where conditions may be just right to allow the presence of liquid water on the surface.

NASA explains that TESS observes large regions of the sky known as sectors for 27 days at a time.

TESS identifies and tracks changes in stellar brightness caused by an orbiting planet passing in front of its star.

During recent observations, TESS tracked a total of three planets.

The closest to the star, TOI 700 b is Earth-sized, rocky and has an orbit of ten days.

The middle planet, TOI 700 c, is 2.6 times larger than Earth, likely gas-dominated and orbits every 16 days.

TOI 700 d, the only one in the habitable zone, measures 20 percent larger than Earth and orbits every 37 days.

While the exact conditions on TOI 700 d are unknown, researchers at NASA's Goddard Space Flight Center created models to explore its potential conditions to help narrow future predictions of the planet's atmosphere.

One model showed a water-covered world and the other, a completely dry version of today's earth.

NASA says that future missions, "may be able to identify whether the planets have atmospheres and, if so, even determine their compositions."